The class of polyketides known as epothilones has emerged as a source of potentially therapeutic compounds having modes of action similar to paclitaxel. Interest in the epothilones and epothilone analogs has grown with the observations that certain epothilones are active against tumors that have developed resistance to paclitaxel as well as a reduced potential for undesirable side-effects. Among the epothilones and epothilone analogs being investigated for therapeutic efficacy are the natural product epothilone B, the semi-synthetic epothilone B derivative BMS-247550, also known as ixabepilone, and the synthetic analog EPO-ZK.

Desoxyepothilone B, also known as “epothilone D” is another epothilone derivative having promising anti-tumor properties that is being investigated for therapeutic efficacy. This compound has demonstrated lower toxicity than epothilones having 12,13-epoxides.

More recently analogs of epothilone D having greater in vitro potency have been described, including trans-9,10-dehydroepothilone D ((4S,7R,8S,9S,10E,13Z,16S)-4,8-dihydroxy-5,5,7,9,13-pentamethyl-16-[(1E)-1-methyl-2-(2-methyl-4-thiazolyl)ethenyl]-oxacyclohexadeca-10,13-diene-2,6-dione) and its 26-trifluoro-analog, also known as fludelone. These compounds demonstrate remarkable antitumor activity in mouse xenograft models (Rivkin et al., “Discovery of (E)-9,10-dehydroepothilones through Chemical Synthesis: On the Emergence of 26-Trifluoro-(E)-9,10-dehydro-12,13-desoxyepothilone B as a Promising Anticancer Drug Candidate,” J. Am. Chem. Soc. 126: 10913-10922 (2004).
Although various methods for preparing epothilone derivatives and analogs having anti-tumor activity have been disclosed in the art, including fermentation, semi-synthesis, and total chemical synthesis, there is continuing unmet need for new, more efficient methods for preparing these promising anticancer agents.